Method and apparatus for monitoring the status of non-pollable device in a computer network

Abstract

A network management system includes a user interface, a virtual network and a device communication manager. The virtual network includes models which represent network entities and model relations which represent relations between network entities. Each model includes network data relating to a corresponding network entity and one or more inference handlers for processing the network data to provide user information. The system can poll or communicate with certain network entities and can infer the status of network connectors and other network entities for which polling is impossible or impractical. The system performs a fault isolation technique wherein the fault status of a network device is suppressed when it is determined that the device is not defective. User displays include hierarchical location views and topological views of the network configuration. Network devices are represented on the displays by multifunction icons which permit the user to select additional displays showing detailed information regarding different aspects of the corresponding network device.

What is claimed is: 
     
       1. A method for determining a contact status in a computer network using a network management system, the computer network including a plurality of interconnected network entities including communicating network entities and at least one non-communicating network entity, the network management system executing the steps of: maintaining a virtual network of models of the network entities and model relations representing relations between the network entities, each model including a number of attributes and one or more inference handlers, the attributes being data which define the characteristics of the network entity being modeled, and the inference handler preforming a process on the data upon the occurrence of predetermined events in the model which trigger the inference handler, the attributes including a contact status for the corresponding network entity;   communicating with the communicating network entities to obtain operational information as to the status of the communicating network entities and updating the corresponding contact status attributes in the corresponding models; and   the inference handlers using the operational information as to the communicating network entities and the model relations between the non-communicating network entities and the communicating network entities to infer the contact status of the non-communicating network entity and updating its contact status, said non-communicating network entity being incapable of communicating with the network management system.   
     
     
       2. The method of claim 1, wherein the step of communicating includes polling the communicating network entities at predetermined intervals. 
     
     
       3. The method of claim 2, wherein the polling is performed at different intervals for different communicating network entities. 
     
     
       4. The method of claim 1, wherein the step of using the operational information to infer the contact status of the non-communicating network entity includes monitoring the contact status of models of communicating network entities having a predetermined relation to the non-communicating network entity. 
     
     
       5. The method of claim 1, further including the step providing the contact status of the non-communicating network entity to a user. 
     
     
       6. The method of claim 1, wherein the step of using the operational information to infer the contact status of the non-communicating network entity includes inferring a lost contact status of the non-communicating network entity when all network entities connected to the non-communicating network entity have a lost contact status. 
     
     
       7. The method of claim 1, wherein the step of using the operational information to infer the contact status of the non-communicating network entity includes inferring an established contact status of the non-communicating network entity when at least one network entity connected to the non-communicating network entity has an established contact status. 
     
     
       8. The method of claim 1, wherein the step of using the operational information to infer the contact status of the non-communicating network entity includes inferring an initial contact status of the non-communicating network entity when all network entities connected to the non-communicating network entity have an initial contact status. 
     
     
       9. The method of claim 1, further including the step of updating the models and model relations when a network entity is added to or removed from the network. 
     
     
       10. The method of claim 1, wherein the step of communicating with the communicating network entities includes obtaining operational information as to the status of pores in a ported network entity and updating the contact status of such pores. 
     
     
       11. The method of claim 1, wherein the step of maintaining includes maintaining models and model relations of network entities including network devices, geographical locations of network devices, topological groupings of network devices, and software applications being executed on network devices. 
     
     
       12. The method of claim 1, wherein the step of maintaining includes maintaining model relations of connections between network entities and hierarchial relationships between network entities. 
     
     
       13. The method of claim 1, wherein the inference handlers are triggered by predetermined events including a change in attributes in the same model, a change in attributes in a different model, and predefined events or changes in models or model relations. 
     
     
       14. The method of claim 1, wherein the inference handlers generate an alarm condition when the model attributes meet a predetermined criteria. 
     
     
       15. The method of claim 1, wherein the step of communicating includes automatically receiving operational information without polling. 
     
     
       16. The method of claim 1, wherein the step of maintaining includes maintaining model relations which represent network connections between network devices. 
     
     
       17. The method of claim 1, wherein the step of maintaining includes maintaining model relations that represent hierarchial relations between network entities. 
     
     
       18. The method of claim 1, wherein the step of maintaining includes maintaining location models which represent the parts of a network geographically associated with a building, country, floor, panel, rack, region, room, section, sector, site, or the world. 
     
     
       19. The method of claim 1, wherein the step of maintaining includes maintaining topological models which represent network devices that are topologically associated with a local area network or subnetwork. 
     
     
       20. The method of claim 1, wherein the step of maintaining includes maintaining models that represent components of network devices including circuit boards and ports. 
     
     
       21. The method of claim 1, wherein the step of maintaining includes maintaining models of software applications including data relay, network monitor, terminal server, and end-point operations. 
     
     
       22. The method of claim 1, wherein the step of maintaining includes maintaining an attribute flag which indicates that the data is maintained in the network entity being modeled. 
     
     
       23. The method of claim 1, wherein the step of using the operational information includes the inference handlers producing an output including one or more of attribute changes, creation or destruction of models, and alarms. 
     
     
       24. The method of claim 4, wherein the step of monitoring is performed by an inference handler watching an attribute in another model. 
     
     
       25. The method of claim 1, wherein the operational information obtained for each model is processed by the inference handlers for that model and by inference handlers in other models that are watching such information. 
     
     
       26. The method of claim 1, further including the step of providing an icon manager and automatically communicating a change of attribute data to the icon manager for communication to a user. 
     
     
       27. The method of claim 1, wherein the network management system performs on a programmed digital computer. 
     
     
       28. The method of claim 1, further including the step of in response to user selections, the network management system providing topological views showing interconnections between network entities in the computer network, the topological views having a hierarchial relationship. 
     
     
       29. The method of claim 1, further including the step of in response to user selections, the network management system providing location views showing locations of network entities in the computer network, the locations views having a hierarchial relationship.